Gonzalo Fernandez-Castano admitted he was relieved to have the luxury of a three-shot lead at the last after clinching the BMW Masters title in Shanghai
The importance of the Spaniard's chip-in for an unlikely birdie at 17 became apparent when he found sand twice en route to a scrappy double-bogey six at the closing hole.
His tee-shot found a fairway bunker, and he blocked his third into a greenside trap to raise the possibility of a play-off with the fast-finishing Francesco Molinari.
But Fernandez-Castano splashed out to six feet and calmly two-putted to seal a nerve victory in the opening event of the inaugural European Tour Finals Series.
"I knew it wasn't going to be an easy round, especially the way I started," said Fernandez-Castano, who parred the opening six holes before settling his nerves with birdies at seven and eight.
"I started hitting the ball pretty bad but my caddie kept me cool and told me how good I had been hitting the ball through the week and I played fantastic after that.
"On the last I played too conservative and it was a fighting six at the end for sure. I am glad I had a three-shot advantage on the last because I made my life a little complicated on that hole.
"The putting was letting me down a bit but I made a few changes with my coach last week and it has paid off.
"It's perfect timing because it's Ryder Cup qualification period right now. It doesn't get any better than this; first event of the first ever Final Series and I got the victory."
Molinari was six shots off the pace at the start of the day and despite a front nine of 34, his chances looked to have disappeared with a bogey on the 12th.
But the Ryder Cup star eagled the next and then carded four consecutive birdies as he closed with a superb 64 to set the clubhouse target at 10 under par.
"I haven't played really well on the back nine this week, I always got off to a good start and was stalling on the back nine," said the Italian.
"It was another good start today, then I three-putted the ninth and I thought maybe I get everything back on the back nine.
"I made a good birdie on 11, three-putt on 12 again from far away and then hit a great shot on 13 to make eagle and from then on it seemed everything was going in.
"It's a great feeling when you get to play nine holes like that."